Slipshod (adj)
characterized by a lack of care, thought, or organizationS: carelessA: carefulEx: This is a very important task so please do not perform it in a slipshod manner.
Nefarious (adj)
wicked or criminalS: evilA: admirableEx: It's all a trap, masterminded by the nefarious organization
Precursor (n)
a person or thing that comes before another of the same kindS: forerunnerA: successors Ex: Bad breath can be a precursor to bad gums
Impregnable (adj)
unable to be captured or broken intoS: invulnerable A: vulnerableEx: The lofty walls of the castle seemed impregnable.
Grievance (n)
a real or imagined wrong or other cause for complaint or protest, especially unfair treatment.S: injusticeA: commendation Ex: Her chief grievance was the sexual harassment by her boss.